Syrone Wong wongsyrone

Interview Questions: Analysis of Algorithms

3-SUM in quadratic time. Design an algorithm for the 3-SUM problem that takes time proportional to n2 in the worst case. You may assume that you can sort the n integers in time proportional to n2 or better.

Note: these interview questions are ungraded and purely for your own enrichment. To get a hint, submit a solution.

Hint: given an integer x and a sorted array a[] of n distinct integers, design a linear-time algorithm to determine if there exists two distinct indices i and j such that a[i]+a[j]==x.

KVM OSX Guest 10.11 (El Capitan) with Clover

Some notes about this approach:
- An OSX Installer USB drive for Install OS X El Capitan is created
- Clover is then installed on the USB drive
- Clover Configurator is then run on the USB drive
- The USB drive contents are copied to the VM host
- VNC is used to connect to the guest UI
The qxl virtual video device is used (part of the standard kvm qemu install)

	#!/usr/bin/env bash
	export GOPATH=$PWD/transsocks
	GOOS=linux GOARCH=amd64 go build -a -ldflags="-s -w" github.com/cybozu-go/transocks/...
	GOOS=linux GOARCH=amd64 go install -a -ldflags="-s -w" github.com/cybozu-go/transocks/...

	两台电脑均从救援/备用系统启动，并挂掉原/新根目录到 /mnt。联网并在旧系统启动 sshd，然后：

	```
	rsync -aviHAXKh --partial --delete old_computer:/mnt /mnt
	```

	然后装引导、写引导配置，改 /etc/fstab，重启。

	apt-get update && apt-get dist-upgrade -y
	apt autoremove -y

	rm linux*.deb

	# removed due to libc6 unmet dependency
	# curl -O https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.15.67/amd64/linux-headers-5.15.67-051567-generic_5.15.67-051567.202209080732_amd64.deb
	# removed due to libssl3 unmet dependency
	# curl -O https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.15.67/amd64/linux-headers-5.15.67-051567_5.15.67-051567.202209080732_all.deb
	curl -O https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.15.67/amd64/linux-image-unsigned-5.15.67-051567-generic_5.15.67-051567.202209080732_amd64.deb

	import string

	### DO NOT MODIFY THIS FUNCTION ###
	def load_words(file_name):
	'''
	file_name (string): the name of the file containing
	the list of words to load

	Returns: a list of valid words. Words are strings of lowercase letters.

	# The 6.00 Word Game

	import random
	import string

	VOWELS = 'aeiou'
	CONSONANTS = 'bcdfghjklmnpqrstvwxyz'
	HAND_SIZE = 7

	SCRABBLE_LETTER_VALUES = {

	# Hangman game
	#

	# -----------------------------------
	# Helper code
	# You don't need to understand this helper code,
	# but you will have to know how to use the functions
	# (so be sure to read the docstrings!)

	import random

	Golang的包管理有两个特点，一个是去中心化，也就是说，不像Node.js有一个npm，包的仓库可以是任意的代码仓库。一个是代码仓库跟代码本身耦合在一起（比如导入一个包是 "github.com/langresser/websocket"），这个是Golang推荐的工作方式。

	好处是go get命令可以轻易的安装好一个项目的依赖（自动从github上面clone，并放在GOPATH的第一个路径中），坏处是不能进行版本控制，一旦情况复杂起来就力不从心（比如某个第三方库的接口有修改，可能导致A的电脑上能正常运行的，B使用go get执行完反而不能正常运行）。

	下面是我总结的一些工程管理经验。



	1、建立一个golang文件夹，里面包含两个会加入到GOPATH中的文件夹：